Nonwoven webs or sheets such as those made of paper find extensive use in modern society in the context of household cleaning activity. Paper towels, for example, are a staple item of commerce which have long been used to wipe up liquid spills and to remove stains and/or soil from hard surfaces such as window glass, countertops, sinks, porcelain and metal fixtures, walls and the like, and from other surfaces such as carpeting or furniture.
Paper towels products which are especially useful for household cleaning have attributes which include relatively low density, high bulk, acceptable softness, high absorbency for both aqueous and nonaqueous liquids and acceptable strength and integrity, especially when wet. Prior art towel products having such attributes, and processes for their preparation, have been disclosed, for example, in Ayers, U.S. Pat. No. 3,905,863, Issued Sep. 16, 1975; Ayers, U.S. Pat. No. 3,974,025, Issued Aug. 10, 1976; Trokhan, U.S. Pat. No. 4,191,609, Issued Mar. 4, 1980; Wells and Hensler, U.S. Pat. No. 4,440,597, Issued Apr. 3, 1984; Trokhan, U.S. Pat. No. 4,529,840, Issued Jul. 16, 1985; and Trokhan, U.S. Pat. No. 4,637,859, Issued Jan. 20, 1987.
Paper towels, such as those of the types described in the foregoing patents, are especially useful for absorbing and wiping up liquid spills from both hard surfaces and other surfaces such as furniture and carpets. Paper towel products, however, are also frequently used, generally in combination with liquid cleaning solutions or solvents, to remove soil or stains from surfaces to which such soil or stains may be especially securely affixed. Such soil or stains, for example, may include food material which has been baked on to stove, oven, or cooking utensil surfaces, soap scum found in bathtubs and sinks, ink or crayon markings on walls and furniture, and the like. For wiping products especially useful for such soil and stain removal, it is generally desirable to impart at least some degree of abrasivity to the wiping article in order to bring about the loosening and subsequent removal of the soil or stain from the surface to be cleaned.
Hard surface wiping products which contain abrasive material to enhance soil and stain removal performance are known in the art. For example, Wise et al; U.S. Pat. No. 3,382,058; Issued May 7, 1968 describes a disposable scouring pad having an adhesive abrasive composition adhered to a flexible porous base such as paper. Furthermore, Peter et al; European Patent Application, EP-A-211,664, Published Feb. 25, 1987 discloses a layered sheet-like article having at least one surface containing particles of a soft polymeric abrasive material.
Fabrication of abrasive wiping articles, such as those of the types known in the art, is not without its difficulties. The abrasive material which is associated with such articles must be selected so as to be effective at promoting soil loosening and removal but must not be damaging to the surfaces to be cleaned with the article. The abrasive material must furthermore be affixed to the base substrate using means and in a manner which does not adversely affect the softness and absorbency properties of the wiping article but which nevertheless provides acceptably secure attachment of the abrasive material to the substrate. For example, there should be no significant removal or detachment of abrasive particles from the base substrate as the article is being used, even when wiping occurs in the presence of bleach-free cleaning solutions or solvents.
Given the foregoing, there is a continuing need to identify commercially practical, suitably strong cleaning and wiping products which provide superior absorbency for liquids with enhanced ability to remove soil and stains from surfaces to be cleaned therewith. Accordingly, it is an object of the present invention to provide nonwoven, preferably paper-based, abrasive wiping articles which have acceptable wet strength, desirably high absorbent capacity for liquids and especially effective soil and stain removal performance.
It is a further object of the present invention to provide such abrasive wiping articles having abrasive material affixed thereto in a manner which provides acceptable resistance to abrasive material removal during contact with bleach-free cleaning solutions or solvents which may be encountered when the article is used in household cleaning operations.
It is a further object of the present invention to provide such abrasive wiping articles which can be prepared using cost effective means for affixing abrasive material to the base paper substrate from which such articles are formed.